Can someone please help? I am trying to get the Vampire board to boot, but not having any luck. I get weird graphic glitches on my screen. The board boots without the Vampire in place, so no problems there.

Note that I've tried the Vampire with the mounts in place, and I've cleaned all the pins as well.

I'd like to think that PSU being 5.5A on the 5V rail should be enough. The only thing I could think of is Contact with the socket like many suggested or perhaps some electrolytic cap issue that may not have been apparent when you were drawing less current without the Vampire.

Is there any official support in here? (other than friendly board members!)

Well this forum seems to be overlooked by many. Kipper is out of the game for the most part now, so outside of directly getting contact with him there most likely isn't any official support on this forum. I suggest maybe hitting up IRC #apollo-team on Freenode there are a bunch of us with V600 and a few official team members.